MedlinePlus Medical Encyclopedia: Chronic sinusitis

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Chronic sinusitis

The sinuses are surrounded by bone and cartilage and lined with a mucous membrane. Sinusitis occurs when the membranes becomes inflamed and painful, which may be a result of a blocked sinus opening.

Chronic sinusitis is often caused by inflammation and blockage due to physical obstruction such as a deviated septum, misformed bone or cartilage structures such as the nasal conchae (turbinates), or blockage by nasal cysts or polyps.

Update Date: 8/8/2006

Updated by: D. Scott Smith, M.D., MSc, DTM&H, Chief of Infectious Disease & Geographic Medicine, Kaiser Redwood City, CA & Adjunct Assistant Professor, Stanford University. Review provided by VeriMed Healthcare Network.

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